双层土体中土层分界面对CFG桩身剪切应力影响的数值模拟

摘要

In regard to the limiting conditions of CFG pile breaking mechanism study through physical experiments at present, thus numerical simulation idea and methods are designed to study impacts from bistratal soil mass interface position on CFG pile shaft shearing stress. Under the employing of appropriate boundary conditions, using the large general finite element analysis software ANSYS to compute CFG pile composite foundation finds out pile shaft internal stress, analyzes impacts from soil strata interface position on pile shaft shearing stress. From analysis and comparison of stress patterns can get that under a certain condition, when depths of soil strata interface are different, shearing stresses on pile shaft cross section have well marked regularity. Under a stated condition in this paper, generally, the maximum shearing stresses of pile cross section are all found at about 4m. Hoping the highly effective and economic analytic procedure the paper provided is helpful in CFG pile breaking mechanism study.%鉴于目前采用物理实验来研究CFG的断桩机理问题有诸多的条件限制,采用数值模拟的思路和方法来研究双层土体位置对CFG桩身剪切应力的影响.在选用适当的边界条件下,利用大型通用有限元软件ANSYS对CFG桩复合地基进行计算来求解桩身内部应力,分析了土层分界面位置对桩身剪切应力的影响.通过对应力图的分析比较得出,在一定条件下,土层分界面位置深度不同时,桩身截面上剪切应力存在明显的规律.在文中设定的条件下,一般桩身截面最大剪切应力都出现在4m左右的位置.希望本文提供的这种高效经济的分析方法对研究CFG的断桩机理有一定的帮助.